Except that the reason it was unreliable was, I strongly suspect, because its path was so tight, because it was trying to fit a different stopping pattern in on the line.Once again my comments have been taken out of context. As I've already said, this was one train that I happened to find, out of many. The fact that it wasn't reliable is not relevant to any discussion.
I think that you are taking us out of context here as well. The general point that most of us are making here is that the best use of capacity on 2 track lines is to have a reasonably consistant stopping pattern. On a 4 track railway, the ideal is to have 2 stopping patterns, one fast and one slow, and so on. Anything else will reduce capacity. It is, of course, reasonable to have a compromise, and trade off some capacity for mixed stopping pattern, but, on our crowded railways, we are pretty much at the optimum compromise position right now. Adding in extra fast services often means the removal of several slow services. HS2 is a good example of how to solve this issue. Effectively it's a 6 tracking of the WCML, and will allow a 3rd stopping pattern to run - fast trains take HS2, slow trains take the slow lines, and the current fast lines will be mainly used for semi-fast services. Unfortunately HS2 doesn't directly benefit the South West, but it gives a good idea of the level of investment needed to do the job properly. Admittedly our lines aren't quite as busy as the WCML, so you could probably get away with intermittent new high speed bypasses to allow overtaking, but really saving a few minutes from missing a couple of stops isn't going to shift many people onto the rails, a proper time saving is needed.So you're suggesting that ALL trains from London to Newcastle and Edinburgh, should stop at all of those intermediate stations? That is the comparison ...
Personally, I hope that HS2 is such a massive success, and transforms the way that we do business in the UK, that there is a rapid move to build more high-speed lines to serve other parts of the country, and we end up with several sub-hour trains per hour from Bristol and the SW to Birmingham and beyond